The present disclosure relates to solar modules and particularly to thin film solar modules.
Conventional thin film solar modules, such as CIS-based solar modules (e.g., copper indium gallium (di)selenide or copper indium aluminum (di)selenide) (also referred to as “CIGS”), lack effective passivation between the absorber layer and the adjacent CdS buffer layer. The lack of effective passivation provides a shunting path from excessive binaries or defects, such as Mcu+, CuxSe1-x, or CuxS1-x. This in turn limits the ability to improve the open circuit voltage (Voc) and shunting resistance of the device, which limits the ability to enhance the device's bandgap and thus performance.
Further, heretofore the only known effective approach to enhancing the energy bandgap near the GIGS absorber is through sulfur-incorporation or Ga-flattening.